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Cobalt

Other name(s):

General description

In elemental form, it is a hard gray metal. Its only well-recognized function is as a component of vitamin B-12, a vitamin essential for producing red blood cells and maintaining the nervous system.

Cobalt, present in the body only as a component of vitamin B-12, is essential to erythropoiesis, or production of red blood cells.

Cobalt serves some of the same purposes as manganese and zinc. It can replace manganese in the activation of several enzymes (biochemical reaction activators) and it can replace zinc in some biochemical reactions.

Cobalt also participates in the biotin-dependent Krebs-cycle, the process that the body uses to break down sugars into energy.

Medically valid uses

Cobalt, as a component of vitamin B-12, prevents pernicious anemia. Vitamin B-12 is also essential for maintaining the nervous system.

Unsubstantiated claims

There are currently no beneficial claims based upon cobalt as a single element.

Recommended intake

When present in nutritional supplements, cobalt is usually measured in micrograms (mcg). The average adult intake of cobalt is 5 to 8 mcg per day. No safe Recommended Dietary Allowance (RDA) for cobalt has been established yet.

Trace amounts of cobalt are present in most foods. Foods high in vitamin B-12 are the only source of cobalt actively used by the body.

A cobalt deficiency is ultimately also a vitamin B-12 deficiency. Anemia, specifically pernicious anemia, is one of the obvious symptoms of a cobalt deficiency. Numbness, fatigue, tingling in the extremities, and decreased nerve function occur in long-standing pernicious anemia.

Side effects, toxicity, and interactions

Cobalt is toxic to the heart muscle and can result in toxic cardiomyopathy (heart muscle disease) after excessive exposure.

Polycythemia, an increase in red blood cells, may be a symptom of cobalt excess. Untreated polycythemia can result in congestive heart failure.

Excessive intake of cobalt may produce a goiter (enlargement of the thyroid gland) and reduce the activity of the thyroid. Cobalt may cause hyperglycemia (increased blood sugar).

Since cobalt is a key component of vitamin B-12, individuals with Leber's syndrome, a rare eye condition, should not take any nutritional supplements containing vitamin B-12 without first consulting their physician. Vitamin B-12 in the form of cyanocobalamin could contribute to vision loss in those with this syndrome.

Women who are pregnant or breastfeeding should consult a physician before taking any mineral supplements.

There are no known significant food or drug interactions associated with cobalt.

Additional information

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